1. Field of the Invention
The present invention relates to membrane applicators and, more particularly, to an apparatus suited for applying bitumen rolls on roof structures.
2. Description of the Prior Art
Bituminous roofing membranes are typically torch-applied. The roofer holds a torch in his hands and swept the torch across the back side of an unrolled length of bituminous membrane to cause the membrane to adhere to the underlying flat (or low pitch) roof decking surface. In addition to the torch welder, at least two other operators are needed to properly unroll and aligned the membranes in order to provide for uniform and constant longitudinal lap joints along the sides of adjacent laid down membranes. This process is labour intensive and the quality of the membrane installation varies greatly according to the skills and the attention of the operators. Also, this work is physically demanding and often results in injuries. It would thus be beneficial to limit the human intervention in the application of roof membranes.
This problem has been addressed by Flame Engineering Inc who has developed a bitumen membrane applicator known as the “Red Dragon Modified Bitumen Applicator MBA-800”. The applicator comprises a wheeled carriage supporting a bottom roll mount system and a series of propane torches for heating the entire width of the roll while the carriage is being displaced over the deck surface to be covered. One problem associated with such an applicator is that the distance between the torches and the roll or the BTU output must be continuously readjusted to compensate for the reduction of the diameter of the roll as the membrane is being unrolled. If the distance between the roll and the torches is not re-adjusted the portion of the membrane at the end of the roll will be located at a greater distance from the heat source and will thus be less heated, thereby resulting in undesirable variation in the fusion process of the membrane on the deck surface. The Red Dragon applicator also lacks any means for ensuring that the membrane is properly aligned while being applied. Furthermore, the Red Dragon applicator does not provide any means for covering the excess melted bitumen squeezed out from the sides of the membrane while the same is being applied onto the roof surface. This implies that another individual has to pass after the torch welder to cover with granules the excess molten bitumen that has swept out from the sides of the membrane. Furthermore, a gas hose extends between the Red Dragon carriage and the propane tank, which remains in a fixed position on the deck while the applicator is being displaced thereover. This gas hose is cumbersome and constitutes a further obstacle that has to be contoured or displaced by the operator drawing the red dragon applicator over the deck.